Datasheet

ADP2441-EVALZ User Guide UG-407
Rev. 0 | Page 3 of 12
USING THE EVALUATION BOARD
POWERING UP THE EVALUATION BOARD
The ADP2441 evaluation board is provided fully assembled
and tested. Before applying power to the evaluation board,
follow the procedures in this section.
Input Power Source
The power source voltage must not exceed 36 V, the maximum
operation input voltage of the ADP2441.
Make sure the power source is switched off before connecting it
to the ADP2441 evaluation board. Connect the positive
terminal of the power source to the evaluation board V
IN
terminal (T1), and the negative terminal of the power source to
the evaluation board GND terminal (T2). If the power source
includes an ammeter, connect the ammeter in series with the
input source voltage. Connect the positive lead (+) of the power
source to the ammeter positive (+) connection, the negative
lead (−) of the ammeter to the evaluation board V
IN
terminal
(T1), and the negative lead (−) of the power source to the
evaluation board GND terminal (T2).
Output Load
Make sure the evaluation board is switched off before connect-
ing the load. Connect the load directly to the evaluation board,
with the positive (+) load connection to the V
OUT
terminal
(T3) and the negative (−) load connection to the GND terminal
(T4). If an ammeter is used, connect it in series with the load:
connect the positive (+) ammeter terminal to the evaluation
board V
OUT
terminal (T3), the negative (−) ammeter terminal
to the positive (+) load terminal, and the negative (−) load
terminal to the evaluation board GND terminal (T4).
Once the load is connected, make sure it is set to the proper
current before powering the ADP2441 evaluation board. Before
connecting a load to the output of the evaluation board, make
sure that the output voltage does not exceed the maximum
operating voltage range of the load.
Enabling and Disabling the DC-to-DC Switching
Regulator
In the evaluation board, a voltage divider is used to generate
an enable signal for the IC. As soon as voltage is applied to
V
IN
(24 V), IC is enabled.
Alternatively, header TP1 (EN) is available to enable and disable
the evaluation board. To enable the output, connect the header
TP1 to the V
IN
supply or to an external voltage source. To disable
the output connect the header TP1 to the GND.
PGOOD Signals
When the output is enabled and the output voltage, VOUT, is in
regulation, the logic signal at the PGOOD test point is high. In
a typical application, a pull-up resistor from the PGOOD pin to
the external supply is used to generate this logic signal.
On the evaluation board, the pull-up resistor (R7) is available to
connect to the external supply through the jumper (JP1). Test
Point TP2 is available to connect the external supply of 5 V.
Figure 2 PGOOD Signal
External SS/Track Signal
The SS/TRK pin is multipurpose. It can be used either for
tracking the external supply or for soft start.
A header, TRK, is available on the board for connecting an
external signal to be tracked by the regulator output voltage.
Before applying a signal to the TRK header, make sure the
voltage divider resistor values (R10, R11) connected on the
evaluation board are the correct values (see the ADP2441
data sheet).
Alternatively, to program soft start time, a capacitor can be
connected to SS/TRK pin. On the evaluation board, a 10 nF
capacitor, C11, is connected for a soft start time of 6 ms.
Figure 3. Soft Start Signal
PGOOD
TP2: EXTERNAL
SUPPLY: 5V
JP1
10694-001
R7
50kΩ
R10
OPEN
R11
OPEN
C11
10nF
SS
SS/TRK
TRK
10694-002